US 2010/0154362 A1 discloses a method and system for closing and sealing bags, wherein each bag after filling with contents is conveyed along a hot air manifold which applies hot air under pressure to heat an adhesive layer on a first panel of the bag and to heat an adhesive layer on a second panel of the bag. Each of the adhesive layers is heated to an adhesive state at a temperature below the softening point temperature of the polymeric material of the bag. Then the bag is folded to contact the adhesive layers to one another, and the adhesive layers form an adhesive-to-adhesive seal upon application of pressure. The adhesive material can transfer to the hot air manifold and associated mechanisms, causing equipment contamination. It would be desirable for the bags to have the adhesive material located in positions that will minimize transfer of adhesive material to the hot air manifold and associated mechanisms.
US 2010/0158418 A1 discloses a bag made form a polymeric woven tube. One end of the tube is closed and then sealed by being conveyed along a hot air manifold which applies hot air under pressure to heat an adhesive layer on a first panel of the tube and to heat an adhesive layer on a second panel of the tube. Each of the adhesive layers is heated to an adhesive state at a temperature below the softening point temperature of the polymeric material of the tube. Then the tube is folded to contact the adhesive layers with one another and form an adhesive-to-adhesive seal. It would be desirable to fold the tube without displacing or expelling adhesive from the fold, in order to minimize adhesive contamination on surfaces of the tube.